In a mobile communication system comprising a mobile station and a base station, a distance between the mobile station and the base station may be estimated by measuring a received signal strength at the mobile station and the base station. For example, distances between a personal handy phone system (PHS), and one or more base stations can be estimated by mounting a PHS on a moving device and measuring a strength of signals received at the PHS and transmitted through a propagation path from the base stations in a surrounding area. If the propagation path comprises no obstacles it is referred to as Line-Of-Sight (LOS), and if the propagation path comprises obstacles, it is referred to as Non-Line-Of-Sight (NLOS). The distance between a mobile station and a base station may be estimated, if the propagation path is LOS. However, if the propagation path is NLOS, a distance between the mobile station and the base station may be non-optimally estimated.